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An outlier in an independent samples design (2018)
Presentation / Conference
Derrick, B. (2018, September). An outlier in an independent samples design. Paper presented at Royal Statistical Society Conference

There is a flaw with some of the most commonly performed statistical tests. A paradox of the one sample t-test is the contrariwise decrease in the p-value as the value of an outlier increases in the direction of the overall effect. Demonstration of t... Read More about An outlier in an independent samples design.

To preliminary test or not to preliminary test, that is the question (2018)
Presentation / Conference
Derrick, B. (2018, July). To preliminary test or not to preliminary test, that is the question

Despite the consequences of violations to the assumptions of statistical tests, there is often neglect in published works to report on the assumptions of the tests performed. Preliminary testing the assumptions prior to preforming the test is done ro... Read More about To preliminary test or not to preliminary test, that is the question.

Tests for equality of variances between two samples which contain both paired observations and independent observations (2018)
Journal Article
Derrick, B., Ruck, A., Toher, D., & White, P. (2018). Tests for equality of variances between two samples which contain both paired observations and independent observations

Tests for equality of variances between two samples which contain both paired observations and independent observations are explored using simulation. New solutions which make use of all of the available data are put forward. These new approaches are... Read More about Tests for equality of variances between two samples which contain both paired observations and independent observations.

Parametric and non-parametric tests for the comparison of two samples which both include paired and unpaired observations (2018)
Journal Article
Derrick, B., White, P., & Toher, D. (2018). Parametric and non-parametric tests for the comparison of two samples which both include paired and unpaired observations. Journal of modern applied statistical methods : JMASM,

Samples that include both independent and paired observations cause a dilemma for researchers that covers the full breadth of empirical research. Parametric approaches for the comparison of two samples using all available observations are considered,... Read More about Parametric and non-parametric tests for the comparison of two samples which both include paired and unpaired observations.